It is known the braking of aircraft on the ground is provided by brakes installed on the wheels of undercarriage units and by airbrakes capable of increasing the drag of the aircraft and of pressing the latter onto the ground in order to increase the efficiency of the wheel brakes and/or of the thrust reversers, the wheel brakes being controlled by a system capable of taking account of commands coming from the pilot or from an automatic device.
It is also known that controlling an aircraft on the ground, that is to say controlling the yaw of the said aircraft, is principally ensured by the rudder and by the front undercarriage unit, disposed close to the nose of the latter (commonly called the “nose wheel”), but also by differential braking between the sets of wheels disposed on ether side of the longitudinal axis of the aircraft.
In order to brake the aircraft on the ground, the pilot has two pedals mounted on the rudder bar and respectively associated with the brakes of the wheels disposed on either side of the said longitudinal axis: thus, the right pedal can control the brakes disposed on the right hand side of the aircraft and the left pedal can control the brakes disposed on the left hand side of the latter.
It will be noted that such a device has the disadvantage that the differential braking level and the deceleration level are closely related and depend solely on the position of the said pedals.
Moreover, aircraft are known, generally large aircraft, that comprise at least two pairs of undercarriage wheel assemblies, such that the two undercarriage wheel assemblies of each pair are symmetrical with each other with respect to the median longitudinal vertical plane of such an aircraft and that the two undercarriage wheel assemblies (hereafter referred to as close undercarriage wheel assemblies) of one of the said pairs are closer to the said median longitudinal vertical plane than the two undercarriage wheel assemblies (hereafter referred to as distant undercarriage wheel assemblies) of the other one of the said pairs, each wheel of an undercarriage wheel assembly being equipped with an individual brake.